Mercaptans are commonly present in petroleum products. Their foul odor and highly corrosive nature make them the most undesirable sulfur compounds so they should be removed because of environmental issues. Merox process is used for oxidation of mercaptans to disulfide using air in the presence of alkaline solution and Merox catalyst. In this paper, due to lack of information about the kinetic of mercaptan oxidation, the kinetic of conversion of ethyl mercaptan in gasoline and kerosene is studied in order to be able to model and simulate this process. The experiments were carried out in a semi-batch bubble column reactor and it was proved that increasing the temperature, improves the rate of the reaction. The obtained results were analyzed and a correlation for the rate of reaction is suggested. The suggested equation is first-order with respect to mercaptan concentration.